Current methods of monitoring levels in holding tanks are generally directed to mechanical systems, for example, systems that include a float or a sight-glass to determine a tank level. Some other systems include one or more radar based gauges, for example using frequency modulated continuous waves to measure a level of substance in a tank. In some implementations, a frequency sweeping microwave signal is generated by such a system, and a wave is propagated directed down (e.g., vertically) into the tank being measured. Energy reflected by a top surface of a substance in the tank is collected by an antenna. Electronics derive a distance from the gauge to the surface based on a time delay of the reflected signal.
While radar-based systems are accurate, their reliability does not always meet requirements of petroleum refinery operators. In some cases, tank overfills have occurred due to these failures. Therefore, improved methods and systems for tank level management are needed.